1. Field of the Invention
The present invention relates to a workflow scheduler (an information processing apparatus and a program thereof) serving as a process control system for use in a print system that receives a document from a user and outputs (prints and/or binds) the document.
2. Description of the Related Art
The commercial printing industry is an industry that accepts orders for creation of printed matter (e.g., magazines, newspapers, catalogs and advertisements) from third parties (e.g., customers, or clients), creates printed matter that the clients require, delivers the printed matter to the clients, and receives payment for such products. To produce such products, large-scale printing machines, such as offset presses, are now becoming mainstream. Work in such a commercial printing industry involves various processes: document reception, design, layout, comprehensive layout (presentation using output from printers), which is usually shortened to comp, proofing (correction in layout and color), trial impression (proof printing), preparation of plate for printing, printing, postpress processing, dispatch, and the like.
The reason for the presence of the various steps is that the use of the above printing machine requires preparation of the plate for printing, and once the plate for printing has been prepared, correction of the plate is difficult and highly disadvantageous in terms of cost. Therefore, careful proofing, that is, a confirmatory check of layout and color is necessary. In summary, the printing industry requires large-scale printing machines and needs a .certain amount of time and certain kinds of tasks to create printed matter that a client requires. Additionally, individual tasks require expert knowledge, i.e., expertise of skilled laborers.
Recently, with the increasing speed and resolution of electrophotographic printers and inkjet printers, a “Print on Demand” (POD) market has emerged as a competitor of the traditional printing industry. Print on Demand is a technology that aims to be capable of handling jobs with volumes relatively smaller than those handled in traditional printers on short lead times without using larger-scale printers or systems, like offset presses, and that makes full use of digital image forming devices, such as digital copiers, digital multifunction peripherals, and the like, instead of the use of the larger-scale printers and printing methods described above, and realizes digital printing using electronic data.
Compared to the traditional printing industry, such a POD market has become more digitized and computer-controlled, and the POD market is approaching the level of the traditional printing industry to some extent by using computers. Under such circumstances, in the POD market, the “print-for-pay” (PFP) service, which is a print service provided by copy and print shops, and the centralized reproduction department (CRD) service, which is an in-house print service in corporations, are available.
In providers of these print services, persons in charge determine the processing sequence and the processing time of requests from a specified or unspecified large number of customers solely on the basis of their estimates or experience with consideration of the number of printing pages, the delivery time, or restrictions of human and material resources (task assignments). In accordance with the determined schedules, in the case of paper documents, specified documents are copied with copiers, and in the case of electronic documents, specified files are printed out with printers connected to personal computers. Then, the providers perform final checks and collations, and deliver the products to the customers.
The task assignments performed by conventional methods described above are not necessarily efficient. In particular, in the case of a multiple-process task, if processes are closely correlated with one another, executing the correlated processes continuously is more efficient in some cases. However, such an efficient task assignment is difficult when the task assignment is solely dependent on estimates or experience of a person in charge. One way to address this problem is to provide a process control device having a function of allowing a user to intuitively grasp a schedule of the entire printing system and dynamically change a processing date and time and/or a processing subject of each printing job with an intuitive operation, as in Japanese Patent Laid-Open No. 2002-063004.
In the case of a multiple-process task, if processes are closely correlated with one another, executing the correlated processes continuously is more efficient in some cases. According to conventional methods, as discussed in Japanese Patent Laid-Open No. 2002-063004, print jobs are only assigned appropriately to printers on the basis of the schedule of each printer. In a case where various processes (e.g., proof printing, final printing, and postpress processing) are included in a single print order, different devices, such as a printer and a postpress processing device (e.g., folder and cutter), are assigned to the individual processes. According to the scheduling method discussed in Japanese Patent Laid-Open No. 2002-063004, different processes are controlled as independent processes. In other words, this scheduling method does not consider a case in which multiple processes are executed continuously to increase efficiency. Furthermore, according to this scheduling method, all schedules up to the current process are subjected to optimization of the subsequent scheduling. Therefore, even when multiple processes have been optimized in an integral manner, the determination whether schedules can be changed throughout all processes is performed again or the optimization of schedules is performed again at a time when the subsequent process is scheduled.